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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <div id="rel">
        <span key="1">1</span>
        <span key="2">2</span>
        <span key="3">3</span>
        <span key="4">4</span>
    </div>
    <button id="bt">更新节点</button>
</body>

</html>